"Lye is also known as caustic soda, NaOH or sodium hydroxide and is considered a hazardous material. It absorbs water from the air, so the container must be kept airtight and out of reach of children. If it gets on your skin it will feel soapy. If left on your skin it starts to dissolve the epidermis and causes a burn. You can wash it off with running water or soap and water. It will burn very quickly if it splashes in your eyes, so wearing safety glasses is recommended.

USE EXTREME CAUTION: If you plan on using lye to make pretzels or soap or anything else, treat the area you use it as a laboratory area and clean before and after you are done using it. Always use gloves and safety glasses. Wearing long sleeves, pants and close-toed shoes is recommended.

You should dispose of lye according to your county and state hazardous chemical codes. This might include dilution of the solution with water, neutralization with an acid and subsequent dilution, or taking the waste to a disposal facility. You might also keep the lye solution in a tightly closed, non-metallic container, clearly labeled, to use again, although this is not recommended."